Dispenser having air vent clean-out

ABSTRACT

For using dispensers of the type in which a first can of semifluid hand cleaner or similar viscous substance is filled into a dispenser sleeve, and then a second can of the substance is inverted and applied telescopingly over the sleeve, accumulation of the substance in the internal vent tube of a large size dispenser may make it difficult to remove and replace cans, and may interfere with air inflow necessary for dispensing. In the present invention, air inflow, to permit removal of such a first can, is assured by a pull-down piston in the vent tube to drive any clogging substance out through the nozzle passage. On applying a second full can over the sleeve, the cleaned tube permits easy expulsion of intervening air. Even while the tube is clogged, dispensing may proceed normally; a groove leading downward on the outer side of the sleeve permits continuing inflow of air.

United States Patent ['19 Chappell DISPENSER HAVING AIR VENT Koones 220/44 R X Primary Examiner-Robert B. Reeves Assistant Examiner-John P. Shannon [5 7 ABSTRACT For using dispensers of the type in which a first can of semi-fluid hand cleaner or similar viscous substance is filled into a dispenser sleeve, and then a second can of the substance is inverted and applied telescopingly over the sleeve, accumulation of the substance in the internal vent tube of a large size dispenser may make it difficult to-remove and replace cans, and may interfere with air inflow necessary for dispensing. In the present invention, air inflow, to permit removal of such a first can, is assured by a pull-down piston in the vent tube to drive any clogging substance out through the nozzle passage. On applying a second full can over the sleeve, the cleaned tube permits easy expulsion of intervening air. Even while the tube is clogged, dispensing may proceed normally; a groove leading downward on the outer side of the sleeve permits continuing inflow of air.

:1 Claim, 2 Drawing Figures PATENTEDIAY 7 m4 3. 809,293

Ali (Z 58' 2 FIG. I

DISPENSER HAVING VENT CLEAN-OUT BACKGROUND OF THE INVENTION- This invention relates to dispensers for semi-fluid substances, such as hand cleaner packed in cylindrical cans which are applied telescopingly over a sleeve-like wall of a dispenser having an air vent tube, as generally shown in US. Pat. Nos. 2,751,128 and 2,818,998. The present invention has particular applicability in adapting such a dispenser to large capacity telescoping cans.

This type of dispenser requires air inflow for continued dispensing after a can has been fully telescoped on the dispenser sleeve. Without such air inflow, and with the substance itself sealing the space between the sleeve and a fully telescoped can, such substance could not then be dispensed, in the absence of a pressureapplying augur. This dispensing problemcontrasts with dispensing while the can is descending telescopingly over the sleeve; in this phase the semi fluid substance is dispensed without air inflow.

Difficulties in using this type of dispenser, not serious when small size dispensers and cans were used, have been encountered when using large capacity dispensers which accommodate cans of fromabout five to ten pound capacity. These difficulties have been as follows: When a first can has been'inverted over the dispenser sleeve and its contents transferred into it and while the sleeve is still quite full, the force required to lift up the emptied inverted can has been too great for ready hanclling. Further, to apply a full can over such substantially full sleeve, and drive out the intervening air, has not only been difficult but sometimes resulted in expulsion of part of the dispenser contents through the nozzle.

[have found that these difficulties arise from accumulation of the substance in the vent tube, from various causes.

SUMMARYOF THE INVENTION In the present invention, such clogging is relieved in two ways. For changing cans, I provide the air vent tube with apull-dow'n piston, to be operated before the inverted can is removed. After cleaning out the tube with the piston, when the maintenance man starts to lift the can, air mayflow upward through the tube, to permit the can to be raised. Likewise a replacement can may be easily forced down over the dispenser sleeve, forcing out air through the clean tube. For air inflowv during operations after the dispenser can has bottomed on the.

sleeve edge, accumulation of substance in the vent tube does not require any clean-out. Instead I provide an airflow inlet groove in the side of the sleeve; through it air may enter as the substance is gradually dispensed.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENT A dispenser generally designated 10 and incorporating the preferred embodiment of the present invention,

.is designed specifically for dispensing semi-fluid creamlike hand cleaner of fairly viscous consistency. Such hand cleaner may be marketed in a cylindrical can generally designated a, to fit telescopingly downward over the outside of a vertical cylindrical dispenser sleeve 1 1, sized to fit slidingly within the can.

The principal member of the dispenser 10 is a dispenser base generally designated 12, preferably formed of cast aluminum. Below a sleeve-receiving flange 14, the base 12 has a thick bottom 15 which in effect closes the lower end of the sleeve 11.

The means to discharge the dispenser contents through the base 12 are conventional, and are'best seen in FIG. 1. Set in a vertical passage 17 in the bottom 15, near the rear of the base 12, is a ball check valve 18 which opens into a horizontal cylindrical passage 19 in which is fitted a main operating piston 20 having an O- ring seal 21. At the rear of the end of the passage is second ball checkvalve 22, having a spring 23 to urge it closed. Beyond the second ball check valve 22, a downward and forward extending dispensing passage 25,

leads to a vertical nozzle passage 26, formed in a nozzle 27 which extendsdownwardly along a vertical axis which intersects the central axis of the horizontal cylindrical passage 19. At the intersection of these passages, I provide a laterally enlarged chamber 30 as seen in FIG. 2. The forward end of the horizontal cylindrical passage is closed by the forward threaded end 32 of a rod guide 33 having an O-ringseal 34 aft of the chamber 30. The forward threaded end 32 is mounted in the tapped forward opening 38 of the cylindrical passage 19, as seen in FIG. 1, and secured by a lock nut 36.

Through a drilled bore in the guide 33, a closely fitted discharge rod 40 passes; on its projecting forward end is a handle 41 to reciprocate the operating piston 20 within the cylindrical passage 19, by moving it from its normally closed position shown in solid lines in FIG. 1 to an extreme forward position there shown in phantom lines, and thenreturning it backward to the solid line position. By such operation, the substance in the dispenser sleeve 11 is to be drawn through the first check valve 18 into the passage 19 as the piston 20 is pulled out. When it is pressed backward, its pressure on the substance in the passage 19 closes the first check valve 18 and forces the substance back through the second check valve 22, driving it through the dispensing passage 25 forwardly to and through the downward passage 26 in the dispensing nozzle 27.

In the present invention, as illustrated in FIG. 2, the laterally enlarged chamber 30 extends sideward, serving as a cross-flow portion to intersect the lower end of an upper passage portion 43'which extends downward from a well 44 in the upper surface of the dispenser bottom 15. In the well 44 is concentrically mounted a vertical air vent tube 45 having horizontal air vent passages 46 through its side wall at various elevations. Aligned vertically with the upper passage portion 43 and extending downwardly from the lateral chamber 30 to the exterior of the base 12 is a narrow bored cable passage 47.

The air vent tube 45 is generally of the type shown in saidprior US. Pat. No. 2,818,998. However, at its upper end is a circular sheet metal casing 48 shown broken away in FIG. 2. Mounted within the casing 48 on a forward and aft axis is a spring-returned reel 50 on which a flexible chain 51 is wound. A tangential outlet 52 of the casing 48 extends downward for mounting within the upper end of the vent tube 45. At the end of the chain 51 within the vent tube 45 is a cylindrical clean-out piston 55, having at its lower end a projecting neck 56 in which is crimped the upper end of the cable 57. The cable 57 extends downward through the vent tube 45 and upper passage portion 43 and through the left side of the laterally enlarged chamber 30 as seen in FIG. 2, and thence down through the narrow cable passage 47 to the exterior, where its end has a small pull ring 58.

The clean-out piston 55 and its pull cable 57 serve to clean out the vent tube, for the reasons hereinafter described, by pulling it downward from its uppermost FIG. 1 position to the clean-out position shown in phantom lines in FIG. '2, from whichit is returned upwardly'by the chain 51 pulled by its spring-operated reel 50. I

The sleeve 11 held in the flange 14 of the base 12 has an outer diameter sized to permit close telescoping fit of a cylindrical can a. However, at its back side the sleeve 11 is not precisely cylindrical; it has a vertical groove 59 which may be rolled or formed in any other convenient manner, extending upwardly from the dispenser base flange 14 to an'upper end air-flow notch 60 which communicateswith the inside of the sleeve.

The dispenser base 1 2 is mounted to a back plate 62 by counter-sunk screws 63. The back plate 62 abuts against a short threaded member64 which closes the second check valve 22 in place at the back end of the horizontal passage l9. The back plate 62 is used for mounting the dispenser on a wall or standard, at a convenient height for use.

out those of its apertures 46 above the level of the substance within the sleeve 11.

After the can a has been removed, a similar can filled with the semi-fluid substance may be positioned inverted over the sleeve 11 and pressed downward. In so doing, air above the level of fill within the sleeve will have to be forced out through those apertures 46 above the substance in the sleeve 11.

Should the vent tube 45 become clogged during that phase of dispensing after the can a has bottomed on the sleeve 11, air may nevertheless enter to maintain the atmospheric pressure within the dispenser 10, so that dispensing may continue unimpeded. Such air will enter the groove 59 at its lower end and enter the sleeve 11 through the notch 60. If any substance adhering to the bottom of the can a blocks the notch 60, the partial vacuum created by drawing the plunger 40 outward will dislodge it, permitting air inflow as shown by the arrow in FIG. 1. Thus there is no need to clean out the vent tube 45 except immediately prior to removing an emptied can a.

The present invention thus overcomes the obstacles which have heretofore required pressure augurs, or other pressure-applying mechanism, to squeeze semifluid substances from large-capacity dispensers.

I claim:

1. A dispenser for semi-fluid substancespacked in cylindrical cans, comprising The figures illustrate a typical condition of such a dispenser after use to the extent that the can a has fully telescoped, to rest on the upper edge of the dispenser sleeve 1 l, with some of the substance still adhering to the inverted can bottom b. If a maintenance man then attempts to replace the can a with a ful,l=can, with the sleeve 11 still nearly full, he may encounter difficulty. Specifically, the venttube apertures 46 may be sealed off by clogging at or below them; likewise the vertical groove 59 may be sealed off.

The clogging tendency so described is not entirely predictable. It varies with the viscosity of the substance to be dispensed, the extent to which it may liquefy with exposure to air, and the rate at which it is used. When such clogging does occur, it proves to be of serious difficulty. Thus with the atmospheric pressure of the air exerted down on the can bottom b, the maintenance man will not find it possible to lift the can a until he can break the sealing'tendency of the. substance in the vent tube 45 and groove 59.

In the present invention, the maintenance man simply pulls downward on the ring 58 and permits it to be retracted upward by the spring reel 50. On pulling the through the enlarged chamber 30 and down through the nozzle passage 26. Thereafter the can a may be lifted, the air flowing in readily through the tube 45 and a substantially vertical cylindrical sleeve whose outer diameter is sized to fit slidingly within such a cylindrical can, 7

a dispenser base closing the lower end of said sleeve, said base including means to discharge the sleeve contents therethrough including a nozzle having a discharge passage, and

a tubular air vent tube having'a substantially vertical axis and lateral air passages at a plurality of levels, the air vent tube being mounted to extend upwardly from said dispenser base into the upper portion of the sleeve,

the dispenser base having a connecting passage from the lower end of the air vent tube to an inner part of said nozzle passage,

characterized in that the air vent tube has clean-out means movable downwardly from its upper end to said connecting passage,

whereby to permit removal, from the air vent tube to the nozzle, of such semi-fluid substance which may have accumulated therein, thereby to facilitate air inflow through said'nozzle and' the air vent tube and through its lateral air passages into the disthe said clean-out means includes a piston fitted slidably within said tube and upper passage portions, and the piston has a pull cable extending downwardly along the tube axis through-said vertical passage portions to the exterior and further has return spring means connected to the upper end of the vent tube. 

1. A dispenser for semi-fluid substances packed in cylindrical cans, comprising a substantially vertical cylindrical sleeve whose outer diameter is sized to fit slidingly within such a cylindrical can, a dispenser base closing the lower end of said sleeve, said base including means to discharge the sleeve contents therethrough including a nozzle having a discharge passage, and a tubular air vent tube having a substantially vertical axis and lateral air passages at a plurality of levels, the air vent tube being mounted to extend upwardly from said dispenser base into the upper portion of the sleeve, the dispenser base having a connecting passage from the lower end of the air vent tube to an inner part of said nozzle passage, characterized in that the air vent tube has clean-out means movable downwardly from its upper end to said connecting passage, whereby to permit removal, from the air vent tube to the nozzle, of such semi-fluid substance which may have accumulated therein, thereby to facilitate air inflow through said nozzle and the air vent tube and through its lateral air passages into the dispenser sleeve, and wherein the said connecting passage includes an upper passage portion aligned with the axis of said air vent tube, and the air vent tube and the said upper passage portion are offset laterally from the nozzle discharge passage, and the connecting passage further includes a cross-flow portion connecting to the nozzle passage, the dispenser base further having a pull cable passage on said vent tube axis extending downwardly beneath said cross-flow portion to the exterior, and wherein the said clean-out means includes a piston fitted slidably within said tube and upper passage portions, and the piston has a pull cable extending downwardly along the tube axis through said vertical passage portions to the exterior and further has return spring means connected to the upper end of the vent tube. 